Articular cartilage and meniscal cartilage provide the mobile weight bearing surfaces of the knee joint. Damage to these surfaces is generally due to genetic predisposition, trauma, and/or aging. The result is usually the development of chondromalacia, thinning and softening of the articular cartilage, and degenerative tearing of the meniscal cartilage. Various methods of treatment are available to treat these disease processes. Each option usually has specific indications and is accompanied by a list of benefits and deficiencies that may be compared to other options. Nonsteroidal anti-inflammatory drugs (NSAIDS), cortisone injections, arthroscopic debridement, osteotomy, unicompartmental knee replacement, and total knee replacement have all been used to treat the disease depending on the severity of the process.
Currently, there is a void in options used to treat the relatively young patient with moderate to severe chondromalacia involving mainly one compartment of the knee. Some patients cannot tolerate or do not want the risk of potential side effects of NSAIDS. Repeated cortisone injections actually weaken articular cartilage after a long period of time. Arthroscopic debridement alone frequently does not provide long lasting relief of symptoms. Unicompartmental and bicompartmental total knee replacements resect significant amounts of bone and may require revision surgery when mechanical failure occurs. Revision total knee replacement surgery is usually extensive and results in predictably diminished mechanical life expectancy. Therefore, it is best to delay this type of bone resecting surgery as long as possible.